Browned Butter Brownies with Marshmallow

Best brownies ever, especially with the addition of chocolate chips and marshmallow fluff.

2 sticks (1 cup) unsalted butter
7 oz bittersweet chocolate chips
2 T Dutch process cocoa powder, sifted
1⁄2 t kosher salt
1 1⁄2 c granulated sugar
3 eggs, room temperature
1 T vanilla
1 c all-purpose flour
1⁄3 c chocolate chips
1⁄3 c marshmallow fluff

Line a 9x9” cake pan with a sheet of parchment paper and let the excess overhang the pan. Grease or spray parchment. Preheat the oven to 325 degrees.

In a medium heat-proof bowl, combine the chocolate chips, cocoa powder, and salt.

In a medium saucepan, melt the butter over medium high heat. Stir as the butter begins to foam and crackle, and brown bits of butter form and fall to the bottom of the pan. When the crackling sounds stop, the butter should be a rich, amber color. Pour the browned butter into the bowl containing the chocolate. Stir until the chips are completely melted and the mixture is smooth. Set aside to cool slightly.

In the bowl of a stand mixer fitted with the whisk attachment, beat the sugar, eggs, and vanilla for 3 minutes on medium until light and fluffy. Slowly stream the chocolate mixture into the egg mixture with the mixer on medium speed. Beat for 30 seconds more. Fold the flour in with a spatula until just combined.

Spread brownie batter in prepared pan and smooth. Sprinkle chocolate chips on top. Dollop marshmallow fluff on top and swirl into batter using a knife or offset. Transfer the pan to the oven and bake 40-45 minutes, until a cake tester comes out with only a few crumbs. Remove from the oven to a wire rack and cool completely before slicing.